More than a month after news broke that he was arrested for buying cocaine, Rep. Trey Radel (R-Fla.) drew his first serious GOP primary challenger on Tuesday.

Former state Rep. Paige Kreegel, who finished third against Radel in a crowded 2012 primary for the southwest Florida-based 19th District, announced he will try to unseat the embattled congressman again in an Aug. 26 primary.

Radel checked into rehab in November after he was charged with misdemeanor possession of cocaine. But he has declined to resign his seat and was expected to make his return to Capitol Hill on Tuesday.

Kreegel, who won 18 percent of the vote in the 2012 race, took a not-so-veiled swipe at Radel’s indiscretions, saying in a statement: “Southwest Florida should expect a congressman who can lead, a congressman without distractions, a congressman they can trust.”

Radel, a freshman, has yet to say whether he will seek a second term. Other challengers could also emerge. Among the Republican candidates mentioned for the seat include former Rep. Connie Mack, who held the seat for four terms before losing a 2012 campaign for Senate.

The district is solidly Republican – Mitt Romney won 61 percent of the vote there – so whoever wins the primary is almost certain to carry the seat in the general election.